Function Calls involved in sending/reading uav data

Hi folks,

I’m trying to understand what series of function calls mission planner makes when sending commands to the UAV. I’d also like to know what series of calls are made in reading telemetry data sent back from the UAV. From looking at the code, I see that the MAVLink class defines methods for reading as well as generating MAVLink packets, but it’s unclear where these are actually used.

In summary, when I open Mission Planner, navigate to the ‘Flight Data’ tab, choose ‘Actions’, and send one of the commands, what function calls or code does Mission Planner execute to perform the task? Similarly if I receive data, what code is being called?